Here's an html version of the slides from my public lecture that I gave in Aspen last week. It's also available as pdf, coming in at a healthy 3MB. I was pretty ambitious, explaining not just the observational situation with respect to dark matter and dark energy, but also going into fermions and bosons, and theoretical ideas of extra dimensions and supersymmetry. It was the first time I gave this particular talk; next time I'll try to take out a couple of slides and go at a more leisurely pace.